1. Field of the Invention
The invention relates to a fluid valve, particularly a hydraulic valve, having a switching magnet detachably mounted on a valve housing.
2. The Prior Art
Valves of this type are known in a variety of configurations whereby the switching magnet is most often fasten to the side of the valve housing in such a manner that the actuation element, regulated by the magnetic coil at the corresponding flow of current, acts directly upon the control or closing elements of the hydraulic valve. The mounting and fastening of the switching magnet is achievedxe2x80x94especially in this connection regarding a square magnet commonly used for many yearsxe2x80x94by using through-going bolts at the corners of the iron housing, which iron housing is necessary for creating the magnetic flow. The thereby necessary very long bolts that are screwed into the valve housing represent a considerable part of manufacturing costs in the production of the housing of the switching magnet as well as the long mounting screws themselves (there are, for example, four housing borings and the corresponding bolts to be manufactured and to be available having measurements of 70 mm in length and approximately 3.5 mm in diameter for switching magnets commonly used in a variety of applications, and housings having a 25xc3x9725 mm outer cross section dimension and a length of approximately 70 mm.)
An additional disadvantage of the arrangement know in the art may be seen in the fact that four bolt connections have to be loosened or to be tightened during assembly and maintenance or during replacement of the switching magnet, and that positioning of the switching magnet is limited to a 90xc2x0 rotation on the respective valve housing so that the bolt connection is again aligned.
It is the object of the present invention to provide an improved fluid valve of the above-mentioned type in such a manner that the disadvantages of the known arrangement of this type are avoided, that especially manufacturing costs are reduced, and that assembly, maintenance, and positioning is made easier.
This object is achieved according to the present invention in a fluid valve of the above-mentioned type in that an essentially annular retaining disk is fastened to the valve housing, which is provided with a first fastening device, and which engages with a second fastening device the supporting housing surrounding the coil of the switching magnet at the opposite side of the valve housing. This retaining disk may thereby be attached to the valve housing before the mounting of the switching magnetxe2x80x94preferably by means of screws independent from the switching magnetxe2x80x94and after this attachment, the switching magnet may be connected and fastened merely by cooperation of the fastening devices. Avoided is any complicated machining of the housing for the switching magnetxe2x80x94this housing must only be provided with a second fastening device at a suitable location which then cooperates with the first fastening device on the retaining disk. This (first) fastening device may be easily designed in a manner know in the art so that a relative rotation is made possible between the valve housing and the switching magnet, and which rotation allows free positioning of the switching magnet in consideration of structural conditions.
In a preferred embodiment of the invention the retaining disk has an engaging projection at its outer circumference and the housing surrounding the coil of the switching magnet has at its inner circumference at least one groove as a fastening device in the form of a snap-on arrangement cooperating with the engaging projection. This makes possible the very simple manufacturing of cooperating snap-on arrangements whereby assembly and dismantling is simplified.
In another embodiment of the invention, the front region of the housing surrounding the switching magnet coil that faces the valve housing may have a slot-shaped recess to receive auxiliary elements attached to the coil, particularly switch elements, whereby the grooves or projections of the retaining disk or the housing are formed to run along the entire remaining circumference, respectively. The slot-like recess of the housing in the region of the circumferential grooves or projections cooperating as a snap-on arrangement makes possible a slightly resilient widening of the housing during the sliding-on (of the housing) onto the retaining disk and it may also serve as a resilient pre-tensioning means for the locked snap-on connection at corresponding dimensioning of the cooperating grooves or projections. Very simple assembly is thereby possible while having a very secure connection between the switching magnet and the valve housing whereby it is unimportant whether the grooves are in the housing and the projections are on the retaining disk or if they are arranged in reverse order as long as there is guaranteed the cooperation of these elements to fasten the housing together with the coil onto the retaining disk and thereby onto the valve housing.
In an additional preferred embodiment of the invention the grooves and projections are rounded off in the form of semicircles in a cross-sectional view, which makes an easy and simple production of the snap-on connection possible, especially in conjunction with the above-discussed slightly resilient expandable front side of the housing of the switching magnet.
The invention will be explained in more detail by embodiment examples and partially illustrated schematically in the drawings.